This study investigates the potential of biogas recovery from used engine oil (UEO) by co-digestion with animals’ manure, including cow dung (CD), poultry manure (PM), and cattle manure (CM). The experimental work was carried out in anaerobic biodigesters at mesophilic conditions (37°C). Two groups of biodigesters were prepared. Each group consisted of 4 digesters. UEO was the main component in the first group of biodigesters with and without inoculum, whereby a mix of UEO and petroleum refinery oily sludge (ROS) was the component in the second group of biodigesters. The results revealed that for UEO-based biodigesters, maximum biogas production was 0.98, 1.23, 1.93, and 0 ml/g VS from UEO±CD, UEO±CM, UEO±PM, and U
... Show MoreLow- and medium-carbon structural steel components face random vibration and dynamic loads (like earthquakes) in many applications. Thus a modification to improve their mechanical properties, essentially damping properties, is required. The present study focuses on improving and developing these properties, significantly dampening properties, without losing the other mechanical properties. The specimens used in the present study are structural steel ribbed bar ISO 6935 subjected to heating temperatures of (850, 950, and 1050) ˚C, and cooling schemes of annealing, normalizing, sand, and quenching was selected. The damping properties of the specimens were measured experimentally with the area under the curve for the loadi
... Show MoreThis research represents a practical attempt applied to calibrate and verify a hydraulic model for the Blue Nile River. The calibration procedures are performed using the observed data for a previous period and comparing them with the calibration results while verification requirements are achieved with the application of the observed data for another future period and comparing them with the verification results. The study objective covered a relationship of the river terrain with the distance between the assumed points of the dam failures along the river length. The computed model values and the observed data should conform to the theoretical analysis and the overall verification performance of the model by comparing i
... Show MoreThis paper presents experimentally a new configuration of shear connector for Steel-Concrete-Steel (SCS) sandwich beams that is derived from truss configuration. It consists of vertical and inclined shear connectors welded together and to cover steel plates infilled with concrete. Nine simply supported SCS beams were tested until the failure under a concentrated central load (three- point bending). The beams were similar in length (1100mm), width (100mm), and the top plate thickness (4mm). The test parameters were; beam thickness (150, 200, 250, and 300mm), the bottom plate thickness (4, and 6mm), the diameter of the shear connectors (10, 12, and 16mm), and the connector spacing (100, 200, and 250mm). The test results sh
... Show MoreThis paper studies the combination of fluid viscous dampers in the outrigger system to add supplementary damping into the structure, which purpose to remove the dependability of the structure to lower variable intrinsic damping. This optimizes the accuracy of the dynamic response and by providing higher level of damping, basically minimizes the wanted stiffness of the structure while at the same time optimizing the achievement.
The modal considered is a 36 storey square high rise reinforced concrete building. By constructing a discrete lumped mass model and using frequency-based response function, two systems of dampers, parallel and series systems are studied. The maximu
... Show MoreMonitoring and analysing of the vertical deformations or the settlements of the structures is one of the main research fields in geodetic applications, which is considered a precise periodic measurement, made at different epochs to investigate these deformations on heavy structures.
In this research, the deformation measurements were carried out on one of Baghdad University buildings,” Building of Computers Department” of dimensions (70.0 * 81.3 m.). Due to some cracks observed in their walls, it was necessary to monitor the vertical displacement of this building at some particular monitoring points by constructing a vertical network and measured in different epochs. The first epoch (zero epoch) was carried out in April 2006, the
Heat transfer process and fluid flow in a solar chimney used for natural ventilation are investigated numerically in the present work. Solar chimney was tested by selecting different positions of absorber namely: at the back side, front side, and at the middle of the air gap. CFD analysis based on finite volume method is used to predict the thermal performance, and air flow in two dimensional solar chimney under unsteady state condition, to identify the effect of different parameters such as solar radiation. Results show that a solar chimney with absorber at the middle of the air gap gives better ventilation performance. A comparison between the numerical and previous experimental results shows fair agreement.
HCl is separated from HCl –H2SO4 solution by membrane distillation process(MD). The flat –sheet membranes made from polyvinylidene fluoride (PVDF) and polypropylene (pp.). Plate and frame these types of membrane where used in the process. The feed is a mixture of HCl and H2SO4 acids compositions depended on metals treated object.HCl concentration increased in the permeate during the process but sulfuric acid increased gradually in the feed .During the concentration of solution acids concentrations in the feed at the beginning were 50 g/dm3 of sulfuric acid and 50 g/dm3 of hydrochloric acid at 333K feed temperature the permeate flux was 71 dm
... Show MoreThe present work is an attempt to develop design data for an Iraqi roof and wall constructions using the latest ASHRAE Radiant Time Series (RTS) cooling load calculation method. The work involves calculation of cooling load theoretically by introducing the design data for Iraq, and verifies the results experimentally by field measurements. Technical specifications of Iraqi construction materials are used to derive the conduction time factors that needed in RTS method calculations. Special software published by Oklahoma state university is used to extract the conduction factors according to the technical specifications of Iraqi construction materials. Good agreement between the average theoretical and measured cooli
... Show MorePermanent deformations (rutting) of asphalt pavements which appear in many roads in Iraq.
have caused a major impact on pavement performance by reducing the useful service life of
pavement and creating services hazards for highway users. Therefore, it is important to analyze and
investigate this type of distress.
The objectives of the present paper include; the analysis of the main contributory factors
influencing rutting, and development of statistical model for the prediction of permanent
deformation in paving materials. To achieved these objectives for the requirements of data collection. five types of gradation. (40-50) asphalt cement and different types of filler are used to prepare three hundred sixty asphalt conc
The present work investigates the effect of some of the variables in spot tungsten inert gas shielded
welding (TIG Spot) for (Aluminum-Magnesium) alloy type(5052-O) which is non–heat treatable
alloy for its wide industrial uses and applications in field of welding technology.
TIG Spot welding was performed by using tungsten electrode (EWTh2)of diameter (3.2mm) and
DC current with direct polarity (DCSP) at constant shielded gas flow rate (15litre/min).
The welded specimens were tested by using the Instron machine to determine the maximum shear
force (shear strength ) of spot welded and to define the optimum conditions of spot welding
variables in relation to the weld current, weld time and arc length of welding to
A new mathematical model for three-dimensional thin-walled curved beam element of closed
section with seven degree-of-freedom per node is derived using the finite element procedure. The
seventh degree-of-freedom is to account for warning restraint effects in thin-walled closed sections.
These effects may become significant and should be fully considered in such sections for which
warping deformations are relatively large. This model considers the coupled action due to the
curved geometry of the element using its exact static behavior in the derivation of the displacement
field. Also, the modei considers the non-uniform torsional behavior of closed thin-walled sections
in cases where additional axial direct stresses a
The research represents an applied study to the urban scene of Baghdad city center within the area of (Al Bab Al Sharqi – Al Tahrir Square) through studying and identifying the levels of the reciprocal correlation of advertising signs impact on urban scene , then finding out the indicators and potential values which have made advertising signs as positive value by achieving the mechanisms of visual quality or a negative value by achieving mechanisms of visual pollution. And then examining the resulted visual perception defect reforming mechanism from it and identify the basic elements represented of the laws and legislation known worldwide. When presenting the problem, The research depends on: (Lack of clear perception
... Show MoreIn the present work effect of recycled heating and cooling on the values of concrete compressive strength due to high temperature of 4000C was studied.
The tests show that the percent of reduction in compressive strength of the samples which exposed to a temperature of 4000C for one cycle was 32.5%, while the reduction was 52.7% for the samples which were exposed to recycled heating and cooling of ten times .
Moreover a study of the effect of specimen sizes on the percentages of compressive strength reduction due to high temperature
... Show MoreSome structures such as tall buildings, offshore platforms, and bridge bents are subjected to lateral loads of considerable magnitude due to wind and wave actions, ship impacts, or high-speed vehicles. Significant torsional forces can be transferred to the foundation piles by virtue of eccentric lateral loading. The testing program of this study includes one group consists of 3 piles, four percentages of allowable vertical load were used (0%, 25%, 50%, and 100%) with two L/D ratios 20 and 30, vertical allowable load 110 N for L/D = 20 and 156 N for L/D = 30. The results obtained indicate that the torsional capacity for pile group increases with increasing the percentage of allowable vertical load, when the percentage of allowable vertica
... Show MoreParticulate matter (PM) emitted from diesel engine exhaust have been measured in terms of mass, using
99.98 % pure ethanol blended directly, without additives, with conventional diesel fuel (gas – oil),to
get 10 % , 15 %, 20 % ethanol emulsions . The resulting PM collected has been compared with those
from straight diesel. The engine used is a stationary single cylinder, variable compression ratio Ricardo
E6/US. This engine is fully instrumented and could run as a compression or spark ignition.
Observations showed that particulate matter (PM) emissions decrease with increasing oxygenate
content in the fuel, with some increase of fuel consumption, which is due to the lower heating value of
ethanol. The reduction in
When embankment is constructed on very soft soil, special construction methods are adopted. One of the techniques is a piled embankment. Piled (stone columns) embankments provide an economic and effective solution to the problem of constructing embankments over soft soils. This method can reduce settlements, construction time and cost. Stone columns provide an effective improvement method for soft soils under light structures such as rail or road embankments. The present work investigates the behavior of the embankment models resting on soft soil reinforced with stone columns. Model tests were performed with different spacing distances between stone columns and two lengths to diameter ratios of the stone columns, in addition to different
... Show MoreElectrochemical processes can provide valuable contributions to the protection of the environment through implementation of effluent treatment and production-integrated processes for the
minimization of waste and toxic compounds. The performance of a novel pilot scale, batch re-cycled, flow-through cell, with stainless steel tubes bundle cathode in the removal of cadmium was investigated utilizing the potential results obtained from a batch mode. The studied electrochemical reaction was the cathodic reduction of Cd+2 using 0.5 M sodium sulphate as supporting electrolyte. The analyzed parameters were different initial Cd+2 concentrations (50,100, 200, 300, 400 ppm) and different electrolyte flow-rates (100, 200, 250, 300, 350 L/hr), th
In the present study, finite difference method is proposed to use for the development of Mathematical model for the prediction of the pavement t
... Show MoreIn this work a high-speed turbopumps of (22000 rpm) rotational speed, which are oxidizer and fuel turbopumps, are designed. The design requirement for mass flow rate and outlet pressure are (12.5 kg/s) and (113×10 Pa) respectively for the oxidizer turbopump, and (3.5 kg/s) and (95x10 Pa) respectively for the fuel turbopump. The design work of centrifugal pump is divided into impeller and volute design works. The impeller design work is performed by the streamline curvature and quasi-orthogonal technique based on hub-to-shroud mean stream surface between two blades with assistance of experimental design coefficients and relations for first prediction. The volute is designed by using the method of constant angular momentum, where in this
... Show MoreThe aim of reducing drag is to increase the flow efficiency by using the same pipes and pumps. As a result the amount of crude oil transported will increase without using new pipes and pumps.
In the present work, the effectiveness of two surfactants (Sodium dodecyl benzene sulfonate (SDBS) and Sodium lauryl sulfate (SLS)) are studied by using a closed loop system. This system consists of three pipes made from commercial steel, each one with different diameter (0.75, 1 and 1.5 inch). The length of each individual test section of the pipe is two meters. The experimental work is achieved under three different temperatures (30º, 40º and 50°C). The concentrations of both surfactants used are ranging between 50 to 300 weight ppm. Laborat
Fluorophosphate neodymium laser glass has been prepared by discontinuous melting technique.
Special melting and casting conditions were followed to prevent devitrification of glass samples.
Furnace melting followed by slow cooling resulted formation of non vitreous glass. Problems of
high viscosity melt and incomplete solubility and immiscibility of glass components were
encountered by adjusting composition of glass components. X-ray diffraction analysis of the
prepared glass samples proved the formation of amorphous phase. The prepared Nd – fluoride glass
has low refractive index which is an important parameter for high power laser application. Optical
properties of Nd – fluoride glass samples were investigated.
The phenomenon of informal building Spread recently in Iraqi residential areas, in general, and in Baghdad, in particular, due to the urgent housing need, on the one hand, and lack of commitment to building controls, on the other hand, to highlight the phenomenon of uncommitted building to controls and housing governing legislation in Iraq, leading to heterogeneity in both building densities and plot areas, and disorder in the urban fabric and urban escape of those areas. Research problem identified as the absence of a clear vision about the General aspects of the phenomenon of informal building in residential street scene, and the role of designed housing projects as a substitute for informal building in built residential areas. The des
... Show Morepole assignment technique specifies all closed-loop poles. Such a system where the reference input always zero is called a regulator system. The problem of shifting the regulator poles (closed-loop poles) at the desired location is called pole assignment problem, and this can be done if and only if the system is completely state controllable. Controller's objective is to maintain the speed of rotation of the motor shaft with a particular step response. Results obtained were compared with another controller applied to the DC motor based on Proportional Integral Derivative (PID) control. The controller was designed and tested using MATLAB 7 programming language.
New fast sealed lead acid (SLA) battery chargers must be able to charge the fully discharged
batteries in a short time. In the same time, the charger must monitor the battery state of health in
order to prevent over charge and to extend the battery life time.
In this paper a Fast charger was presented to charge SLA batteries in short time and monitor the
battery voltage to prevent over charge. The design was implemented practically. And 150 charger of
similar type was produced for commercial use. They are now in service in different Mobile base
station sites around Baghdad. It can charge a fully discharged 12V, 4.5Ah battery in less than 5
hours. To supply PLC control system on DC power to about 24 hour of continuous
This study investigates the effects of the presences of harmonics in the exciting voltage
when using a dc/ac inverter on the performance of a single-phase induction motor, the
investigation includes theoretical and experimental parts and together with performance
comparison of the motor with the nominal sinusoidal input voltage. The computed
performance of the motor depend on the theoretical equivalent circuits which are modified
to take into account the existence of harmonics in the inverter output to compute the
performance at each harmonic order. It conclude from the analysis that the pulsating torque
is inherent in single-phase induction motor even when supplied from a sinusoidal voltage
source. Particular att
Anumerical solutions is presented to investigate the effect of inclination angle (θ) , perforation ratio (m) and wall temperature of the plate (Tw) on the heat transfer in natural convection from isothermal square flat plate up surface heated (with and without concentrated hole). The flat plate with dimensions of (128 mm) length × (64 mm) width has been used five with square models of the flat plate that gave a rectangular perforation of (m=0.03, 0.06, 0.13, 0.25, 0.5). The values of angle of inclination were (0o, 15o 30o 45o 60o) from horizontal position and the values of wall temperature (50oC, 60 oC, 70 oC, 90 oC, 100o<
... Show MoreAshShinnafiyah and AsSamawa cities suffer from significant increase in salinity of Euphrates River water compared with their counterpart's north AshShinnafiyah city which is reflected adversely on the quality of water within the study area. The study aims to find possible solutions to avoid the deterioration of Euphrates River northern AshShinnafiyah city until AsSamawa city that were
presented by total dissolved solid TDS. Twelve main hydrological and fifteen salinity measurement stations were selected to cover 117 km of the river reach within the study area during July-2011. Additional twenty three hydrological and salinity stations were adopted during March-2012, winter season to the river within the study area. After conducting t
Airborne radioactive particulates (for both indoor and outdoor air), in Al-Jaderiya region (Baghdad), have been collected to measure the concentration of Radon-222 daughter products of gamma ray emission (214Pb, 214Bi and 218Po) and hence calculate the concentration of Radon-222. 24 samples were analyzed (12 indoor and others outdoor), using gamma ray spectrometric system based on a High purity Germanium detector (HpGe) of (40%) efficiency. The average concentrations of Radon-222, were found to be (93.7 Bq/m
... Show MoreThe present work divided into two parts, first the experimental side which included the
measuring of the first natural frequency for the notched and unnotched cantilever composite beams
which consisted of four symmetrical layers and made of Kevlar- epoxy reinforced. A numerical
study covers the effect of notches on the natural frequencies of the same specimen used in the
experimental part. The mathematical model for the beam contains two open edges on the upper
surface. The effect of the location of cracks relative to the restricted end, depth of cracks, volume
fraction of fibers and orientation of the fiber on the natural frequencies are explored. The results
were calculated using the known engineering program (ANSY